Our Shortstop Born in the 1990s is Probably Better than Your Shortstop Born in the 1990s

When top prospect Starlin Castro was called up a few weeks ago, one of the biggest question marks was his plate discipline. Kevin Goldstein, from Baseball Prospectus:

Castro still has some holes in his game, the biggest one being plate discipline. Castro has drawn just two walks this year, and since the beginning of last season, has worked just 31 walks in 136 games. He's a free swinger who needs to learn how to work the count against more advanced pitching. (4/19/2010)

Let's take a very early look at Starlin Castro's plate discipline through his first two weeks as a major league shortstop. 

I first thought of taking a deeper look at Castro's swing and contact percentages after seeing this RBI single last week against the Rockies:



Here's Castro's swing percentages for pitches outside (O) and inside (Z) the strike zone this season, with league averages in parentheses:

O-Swing%: 25.6 (27.5)
Z-Swing%: 61.8 (63.6)
Swing%: 43.5 (44.7)

(All data from Fangraphs)

He's certainly not a hacker (or "free swinger") by any means, either inside or outside the strike zone. Contrast him with another Cubs' rookie, Tyler Colvin, who swings at 37% of pitches outside the strike zone. Also of note, the only Cub who swings at less pitches inside the strike zone is Geovany Soto, who quite frankly doesn't swing at anything (33.3 Swing%, 2nd in all of baseball).

So in terms of the pitches he chooses to swing at, Castro is right in line with league averages thus far. How does he fare in making contact with those pitches?

O-Contact%: 90.0 (65.4)
Z-Contact%: 91.5 (88.2)
Contact%: 91.0 (80.9)

The number that obviously stands out is his ridiculous O-Contact rate. Among players with a minimum 50 PA this season, Castro ranks fifth in all of baseball. The average MLB hitter so far this season has made contact 65% of the time when they swing at a ball outside the strike zone. Castro has 90% of the time. His 91% overall contact percentage is tops on the Cubs.

So in his first two weeks in the major leagues, Starlin Castro has been swinging at pitches both inside and outside the zone at a perfectly acceptable rate, but has been making an above-average amount of contact. Has Castro been harmed by making more contact with "bad" pitches? His .405 BABIP, 21.5 LD% and .408 wOBA seemingly say otherwise.

Is Starlin Castro just whacking easy pitches to hit? Not only has he spent nearly all of his two weeks in the majors batting 8th, but only Alfonso Soriano (45.3%) and Jeff Baker (50.5%) have seen fastballs at a lower rate than Castro (51.9%). He also gets sliders 20.9% of the time, highest on the team. So...no, he isn't feasting on simple pitches.

These numbers seem to confirm what a lot of smart people in the Cubs community think: Starlin Castro is just really freaking good at hitting baseballs, and doesn't draw a lot of walks because of it. Perhaps one of the reasons he wasn't taking many free passes at AA is because he was too busy OPSing .990, and hitting the crap out of everything in sight because he can.

The sample size is obviously small here, but the combination of my eyes and my spreadsheets tells me that Starlin Castro, at age 20, is not in any way overwhelmed by major league pitching. Maybe that will change over the season as teams get better scouting reports on him (early numbers show us he struggles with cutters and changeups).

The one area that he obviously can improve in is power*. Castro only has one extra base hit since his ridiculous debut in Cincinnatti. But again, he's freaking 20 years old. He was born five months after the Berlin Wall came down. Let's let that frame build a little. If in five years he has the plate discipline of Luis Castillo but adds some of the power of Miguel Tejada, I'll certainly take it. It'll be more than worth the wait.

*OMG WAT you statf*g did you even watch his debut?